Date of Graduation
5-2016
Document Type
Thesis
Degree Name
Master of Science in Geology (MS)
Degree Level
Graduate
Department
Geosciences
Advisor/Mentor
Manger, Walter L.
Committee Member
Potra, Adriana
Second Committee Member
Pollock, Erik D.
Third Committee Member
Zachry, Doy L.
Keywords
Earth sciences; Arkansas novaculite; Boone formation; Chert; Novaculite; Silica source; Volcanic; silica
Abstract
Geochemical analyses of the Arkansas Novaculite, located within core structures of the Ouachita Mountains in west-central Arkansas, and penecontemporaneous chert of the lower Boone Formation, located atop the Springfield Plateau of southwest Missouri, northwest Arkansas, and northeast Oklahoma, have identified a significant concentration of both aluminum and potassium. This would seem to eliminate a biogenic origin and favor a volcanic source of the silica that comprises these units. Trace and rare earth element (REE) analysis also suggests that the Arkansas Novaculite and the chert in the lower Boone Formation may have both been formed from the same volcanic source.
The volcanic signatures of these two formations were compared to average elemental concentrations of continental, Aleutian, and boninite magmatic bodies. Both the Arkansas Novaculite and Boone Formation resemble a boninitic magmatic body in composition. Second order mantle melt needed to create this titanium depleted primitive andesitic body would have been generated as the Gondwana landmass approached the North American craton throughout the Devonian and Lower Mississippian periods, eventually closing the Ouachita Trough during the Ouachita Orogeny (Pennsylvanian).
Field samples of the Arkansas Novaculite were collected at Caddo Gap, Arkansas, while the Boone Formation was sampled across southwest Missouri and northwest Arkansas. Both the energy-dispersive X-ray and mass spectrometry analysis was performed at the University of Arkansas’ Nano-Bio Materials Characterization Facility and Department of Chemistry, respectively.
Citation
Philbrick, J. B. (2016). A Geochemical Analysis of the Arkansas Novaculite and Comparison to the Siliceous Deposits of the Boone Formation. Graduate Theses and Dissertations Retrieved from https://scholarworks.uark.edu/etd/1520
